Antitheft unit



FIG. 1 is a front elevational view of an antitheft unit showing my new design;

FIG. 2 is an enlarged perspective view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a side elevational view taken from the right of FIG. 1. 

The ornamental design for an antitheft unit, as shown. 